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local variable scope

Method- local variable

Local variables inside a method is not accessible outside the method.

Eg:

def method
  x = 2
end

 puts x

This will result in an error .

To access variables outside a method. You need to pass in parameters/arguments into the method.

 x = ''
def method(x)
  x = 2
end

 puts method(x)

 However, in this case, x is still ' ' . The puts only print the return value of the method , which is 2. 
The method do not mutate the caller.

Local variable - block scope.

Local variable that sits outside a block is ACCESSIBLE to inside the block. While local variable that is initialize inside a block is NOT ACCESSIBLE outside the block.

Eg:

 x = "Hello"

 loop do
   puts x
   break
end

This is ok

Eg:

loop do 
   x = "Hello"
   break
end

 puts x

This will result in an error.

 PS: Please take note that IF statement is not considered a block. Therefore any variables initialized in an IF statement is accessible outside the method.



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